Peripheral Ventricular Assist Devices in Interventional Cardiology: The Impella® Micro-Axial Pump

Coronary artery disease (CAD) presents an ever-growing burden on health systems especially in the Western world. While percutaneous coronary intervention (PCI) is feasible in increasingly complex CAD, certain patient groups possess a high risk for major cardiac adverse events (MACE) during PCI. Poor outcome is associated with significantly depressed left ventricular function, complexity of relevant lesions, and increasing incidence of pre-existing cerebrovascular comorbidities and poor pre-interventional status. However, these risk factors also translate into a high peri-operative risk for coronary artery bypass graft (CABG) rendering some of these patients inoperable. Peripheral ventricular assist devices (pVADs) are temporarily inserted axial or centrifugal pumps that support ventricular output during PCI. The Impella® micro-axial device (Abiomed, Danvers, Massachusetts, USA) is an easily implantable pVAD that may improve patient outcome during PCI in high-risk patients (termed “protected PCI”) and in patients with cardiogenic shock (CS). pVADs in general and the Impella® system in particular play important roles in interventional cardiology and its indications and use will likely expand in the future. This chapter outlines in detail the indications, applications, and future trends concerning the Impella® system. Practical advice is given on the correct implantation of the device

Prognostic value of negative stress cardiac magnetic resonance imaging in patients with moderate-severe coronary artery stenosis

ObjectiveThis study aims to evaluate the prognostic value of stress cardiac magnetic resonance (CMR) without inducible ischemia in a real-world cohort of patients with known severe coronary artery stenosis.BackgroundThe prognosis of patients with severe coronary artery stenosis and without inducible ischemia using stress CMR remains uncertain, even though its identification of functionally significant coronary artery disease (CAD) is excellent.Materials and methodsPatients without inducible ischemia and known CAD who underwent stress CMR between February 2015 and December 2016 were included in this retrospective study. These patients were divided into two groups: group 1 with stenosis of 50%–75% and group 2 with stenosis of >75%. The primary endpoint was defined as the occurrence of a major adverse cardiovascular event (MACE) [cardiac death, non-fatal myocardial infarction (MI), percutaneous coronary intervention (PCI), or coronary artery bypass grafting (CABG)].ResultsReal-world data collected from 169 patients with a median age of 69 (60–75) years were included. The median follow-up was 5.5 (IQR 4.1–6.6) years. Events occurred after a mean time of 3.0 ± 2.2 years in group 1 and 3.7 ± 2.0 years in group 2 (p = 0.35). Sixteen (18.8%) patients in group 1 and 23 (27.4%) patients in group 2 suffered from MACE without a significant difference between the two groups (p = 0.33). In group 2, one cardiac death (1.2%), seven non-fatal MI (8.3%), 15 PCI (17.9%), and one CABG (1.2%) occurred.ConclusionThe findings of this pilot study suggest that long-term outcomes in a real-world patient cohort with known severe and moderate coronary artery stenosis but without inducible ischemia were similar. Stress CMR may provide valuable risk stratification in patients with angiographically significant but hemodynamically non-obstructive coronary lesions

Follow-up of iatrogenic aorto-coronary "Dunning" dissections by cardiac computed tomography imaging

Background: Iatrogenic aorto-coronary dissections following percutaneous coronary interventions (PCI) represent a rare but potentially life threatening complication. This restrospective and observational study aims to describe our in-house experience for timely diagnostics and therapy including cardiovascular imaging to follow-up securely high-risk patients with Dunning dissections. Methods: Dunning dissections (DD) occurred during clinical routine PCIs, which were indicated according to current ESC guidelines. Diagnostic assessment, treatment and follow-up were based on coronary angiography with PCI or conservative treatment and cardiac computed tomography (cCTA) imaging. Results: A total of eight patients with iatrogenic DD were included. Median age was 69 years (IQR 65.8–74.5). Patients revealed a coronary multi-vessel-disease in 75% with a median SYNTAX-II-score of 35.3 (IQR 30.2–41.2). The most common type of DD was type III (50%), followed by type I (38%) and type II (13%). In most patients (88%) the DD involved the right coronary arterial ostium. 63% were treated by PCI, the remaining patients were treated conservatively. 88% of patients received at least one cCTA within 2 days, 50% were additionally followed-up by cCTA within a median of 6 months (range: 4–8 months) without any residual. Conclusion: Independently of the type of DD (I-III) it was demonstrated that cCTA represents a valuable imaging modality for detection and follow-up of patients with DDs

Myocardial T1-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI

Background: Myocardial T1-mapping recently emerged as a promising quantitative method for non-invasive tissue characterization in numerous cardiomyopathies. Commonly performed with an inversion-recovery (IR) magnetization preparation at 1.5T, the application at 3T has gained due to increased quantification precision. Alternatively, saturation-recovery (SR) T1-mapping has recently been introduced at 1.5T for improved accuracy. Thus, the purpose of this study is to investigate the robustness and precision of SR T1-mapping at 3T and to establish accurate reference values for native T1-times and extracellular volume fraction (ECV) of healthy myocardium. Methods: Balanced Steady-State Free-Precession (bSSFP) Saturation-Pulse Prepared Heart-rate independent Inversion-REcovery (SAPPHIRE) and Saturation-recovery Single-SHot Acquisition (SASHA) T1-mapping were compared with the Modified Look-Locker inversion recovery (MOLLI) sequence at 3T. Accuracy and precision were studied in phantom. Native and post-contrast T1-times and regional ECV were determined in 20 healthy subjects (10 men, 27 ± 5 years). Subjective image quality, susceptibility artifact rating, in-vivo precision and reproducibility were analyzed. Results: SR T1-mapping showed  0.19; intra: p > 0.09) or consistency (inter: p > 0.07; intra: p > 0.17) between the three methods. Conclusions: Saturation-recovery T1-mapping at 3T yields higher accuracy, comparable inter-subject, inter- and intra-observer variability and less than 30 % precision-loss compared to MOLLI